| Title | Publisher | Year | Language | Documents |
|---|---|---|---|---|
| Old Father Time | Bug-Byte Software | 1983 | English | Solution, Map, Hints |
| On the Adventure Trail | Prentice Hall | 1984 | English | Solution |
| On the Way to the Interview | Commodore Computing International |
1983 | English | Solution |
| Opal Lily, The | McGraw-Hill Book Company UK | 1984 | English | Solution |
| Operation Kristos | Computer and Video Games | 1986 | English | Solution |
| Operation Safras | Shards Software | 1983 | English | Solution |
| Orb, The | A&B Computing | 1986 | English | Solution |
| Orion Quest, The | Argus Press Software, Mind Games | 1984 | English | Solution, Map |
| Oxbridge | Tynesoft | 1986 | English | Solution, Hints |